<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<!--开始标签-->
<body>
    <!--网页上可见的内容写在body里-->
    <!--标签+tab-->
    <p> hell world</p>
    <!--结束标签-->
</body>
</html>